Advanced Squad Leader, more commonly known by its acronym ASL, has been the most successful wargame in the world.  Although Avalon Hill, the company that created it, went bankrupt, the rights were sold to Multi-Man Publishing (MMP) before they went out of business.  Avalon Hill has since been ressurected by Wizards of the Coast, but MMP still owns the game.

I will go over the history of the game, a brief description of it and provide a buying guide.

HISTORY OF THE GAME
The original Squad Leader was an improvement in the popular game Panzer Blitz, which portrayed tank combat in the Easter Front.  Panzer Blitz had platoon sized tank formations, battery sized gun formations, and company sized infantry formations.  Each hex represented 400 meters, or about a quarter mile.  What made Panzer Blitz unique was that it did not attempt to portray a particular battle or unique units.  Instead, it used generic boards and units so that an unlimited number of engagements could be fought.  This was done by picking out the boards that most closely resembled the terrain fought over and by using the counters to represent the actual forces that participated.  Data cards provided all the information to play several different historical battles, called scenarios, or players could easily make their own historical or hypothetical battles.

The map boards were geo-morphic, which meant that the boards could be arranged in any combination desired.  This was achieved by having the half hexagons (half hexes) on the edges of the boards mirror the half hexes opposite them.  When the sides butted up against each other, the two half hexes would form a complete hexagon.  Of course, short sides had to go with short sides and long sides with long sides.

Panzer Blitz gave birth to Panzer Leader, which was the Western Front version of the game, and Arab-Israeli Wars, which added more modern equipment to the mix.  But the most successful of all of these was Squad Leader, and the rest of this article will focus on that.

Squad Leader was intended to do for the infantry what the other games did for armor.  Many of the same concepts (geo-morphic boards, generic counters, scenario cards) were included.  Combat units were reduced to squad sized infantry units with other counters to represent leaders, support weapons, guns and vehicles.  Each hex was reduced to representing 40 meters of real ground and each turn represented 2 minutes of real time.

But by reducing the scale of the action (one mapboard in Squad Leader represented about two hexagons in Panzer Blitz), some innovations and much more detailed rules needed to be included.  The rule book was a whopping 64 pages long.  At that time, a game was considered complex if it had only 8 (those were the days, today card games are more detailed than that).  In order to make it easier to digest, they used Programmed Instruction method where each scenario corresponded to a few pages of rules.  Players could learn new rules at their own pace and then use them in a scenario that was designed especially for it.

The two other major innovations were closely related.  In order to accurately portray the enemy being able to hinder friendly actions, Squad Leader introduced the concept of interactive play by allowing the enemy to fire on friendly forces in the middle of a turn.  This, in turn, resulted in the timing of events to become critical.  Each turn was therefore broken up into phases where each action had a unique time when it could be performed.  The opponent could fire only during the Defensive Fire Phase, which took place after the Movement Phase (this was modified in Advanced Squad Leader, see below).  While phased turns are very common today and computer games even have real time, this was unheard of when Squad Leader came out.

Another innovation I would like to address is that of morale.  I do not consider it a major one because miniatures had long been using rules for morale to show when a unit took too much punishment to continue fighting.  What Squad Leader did do was take this concept to the next logical step.  Rather than have entire companies or regiments just quit the fight at once, in Squad Leader the squads will drop out one by one and it is up to the leaders to rally them.

The original Squad Leader included 12 scenarios, 4 map boards and counter for US, German and Russian forces.  Over time, 3 supplements were designed, plus numerous scenarios and articles appeared in The General (the Avalon Hill game magazine).  The 1st supplement, Cross of Iron, told gamers to throw away all the old tank counters and forget the earlier rules.  Tank warfare was completely overhauled and units representing Axis Minor countries (Hungary and Rumania) were introduced.  The 2nd supplement, Cresendo of Doom, added British, French and Allied Minor countries (with scenarios in Norway, Demark and Holland).  The 3rd, GI: Anvil of Victory, completely overhauled the US forces and introduced the concept of half squads to the game.  The supplements each had 64 pages of additional rules, as well as additional map boards and counters.

Even though the only drastic rule changed happened in Cross of Iron, the constant addition and deletion of rules took its toll.  The earlier scenarios were unplayable with new rules and scenarios appearing in The General needed to specify which rules applied to the game.  To make matters worse, the rules had been added in a hodge podge manner and were therefore scattered throughout four books.  Something needed to change and it did.

Advanced Squad Leader was the result of the change.  Originally, it was intended to simply be a consolidated and well indexed book of all the existing rules.  This would have allowed players to keep their original games.  Instead, they came up with a whole new system that not only re-wrote the rules, but came out with new counters.  The rule book was larger than the previous 4 books and it was promised that even more would come out.

This was not as bad as it may seem.  The map boards, which were hard mounted and the most expensive item in the game boxes, were retained.  The new rule book was very well organized where infantry combat, guns and artillery, vehicles and finally terrain were the most important chapters.  Efforts to keep each chapter as self sustaining as possible were made and cross-references were added.  Examples were plentiful.  Although there was not a Programmed Instruction included originally, cleaver players (or those under guidence by an experienced player) could easily create their own.  Almost half of the infantry chapter covered specialty rules (such as cavalry) that were rarely used, and one only needed to be familiar with the terrain on the boards currently in use, not necessarily every terrain type that existed.  When players felt comfortable with this, they could gradually add new types of equipment and only read the rules necessary for them.  In many ways, the new ASL played smoother than Squad Leader.

The rulebook was not complete by itself.  Ownership of Beyond Valor (or Paratroop), which only had scenarios, boards and counters, was required, as well as boards from the original Squad Leader series.  More modules were created, each one focusing on a particular theme.  They did add counters, boards and scenarios, but only a few contained new rules.  And the modules that did include new rules did not conflict with existing ones.  Instead, they focused on themes not yet covered such as desert fighting, jungle fighting, amphibous landings, air assault and extreme weather.  They did not replace rules, they added to them.

Besides core modules that added more nationalities, specialty modules became available.  Two games, Streets of Fire and Hedrow Hell, were called Deluxe ASL.  The hexagons were the same scale that the popular micro armor (roughly 1/280 scale) miniatures were, so they could be used with the game.  A special line of DASL micro armor was developed by GHQ, but any micro armor line would work just well.  Historical modules focused on regimental sized actions that covered several days.  Players now had to be careful not to win phyric victories, as there would be another fight tomorrow against a reinforced opponent.  There were four such games before Avalon Hill went out of business: Red Barricades (Stalingrad), Kampgruppe Peiper I and II (Battle of the Buldge) and Pegasus Bridge (D-Day).  Avalon Hill published periodicals especially for ASL besides regular features in The General and there was an annual tormament held in Ohio (the ASLOktoberfest).  The Oktoberfest was the only major gaming convention that supported only one game, not even Dungeons & Dragons or Magic: The Gathering has been able to do that.

When MMP bought the rights to the game, they came out with yet two more types of modules.  The first is the Starter Kit modules, complete with simplified rules for beginners to get a feel for the hobby before paying for the more expensive "proper" game (more on that in Buying Guide).  They also came out with Historical Study games.  They have a lot in common with the Historical Modules, but with a subtle difference.  The Historical Modules focused on a particular battle, ideally one that lasted several days in one small spot and both sides had a chance to attack.  The units you fight with today are the survivors of what you had yesterday and how well you did before will influence how well off you are now.  The Historical Study focuses on an entire campaign.  It is basically a history lesson where you take short breaks in the reading to play a scenario that recreates the fighting or at least is typical of the type of combat you just read about.  Engagements will therefore be in many different historical locations and require different maps.  Units may or may not be the same ones you fought with before and how you did in the last battle will not affect the next one.

GAME DESCRIPTION
The game is taken in turns.  When each player has had a turn, then it is said a game turn has passed.  When the number of game turns is over, each player consults the scenario victory conditions to see which side won.

The scenario cards include a picture that, if not from the engagement itself, is representative of something the scenario contains.  All official scenarios are based on historical engagements that range from the Japanese invasion of China in 1933 to the Spanish Civil War to the consoliation of communist power in occupied territories after World War II ended.  Clubs have even adapted the game to fit Korean and Viet Nam conflicts, but that is outside this scope.  Historical data includes events leading up to the fight, as well as the historical outcome of the battle.

The scenario cards identify which map boards are to be used and which configuration to be used.  Overlays are sometimes used, especially in Desert and Pacific Theater games.  The major units that fought for each side are identified, as well as number and quality of the squads, support weapons, guns and vehicles that made them up.  These sub-units are the counters used in the game.  There will also be direction as to which side sets up first and where units can set up.

Each turn has 8 phases:

1) Rally Phase:  Broken units can be rallied so they can fight again.
2) Preperation Fire Phase:  The phasing player can fire his units at enemy units in an attempt to break (make them non-responsive to the other player's wishes) or eliminate them.
3) Movement Phase:  The phasing player may move all, some or none of his units.  Most units can not move into an area occupied by the enemy, although armored vehicles can.  Units that already fired may not move.  The opposing player can shoot at moving units at this time.
4) Defensive Fire Phase:  The opposing player can shoot at the moving player, this time he can shoot at enemy units that did not move.
5) Advancing Fire Phase:  The phasing player can shoot any units that have not yet moved or shot (vehicles can shoot even if they did move).
6) Rout Phase:  Each player may move units that broke their morale away from the enemy.  In some circumstances, units have no  option and must either route or surrender.
7) Advance Phase:  Phasing player can have his Infantry advance one hexagon, even if it is enemy occupied.
8) Close Combat Phase:  Opposing units in the same location use a special chart to eliminate the enemy.  This combat is simultaneous and it is possible that both sides will wipe each other out.

Victory conditions are frequently determined by the number of enemy units eliminated, occupation of certain ground or breaking through (ie-exiting off the opposite side of the board).

There may be those that are familiar with Squad Leader but want to know how ASL compares.  Well, from a playability aspect, ASL is smoother than much of the original Squad Leader.  I would say that anyone who plays Cross of Iron should definately consider ASL.  Anyone who plays Cresendo of Doom needs to switch over unless you like the pain.

The biggest difference to the "feel" of the games comes from two changes: The ratio of leaders to squads and the step reduction system.  In Squad Leader, the Germans had a very high ratio of leaders to squads, sometimes as high as 2 leaders for 3 squads.  The Russians had a pitiful small number of leaders but an overwhelming number of squads, a 1 to 10 was not uncommon.  The Americans were somewhere in the middle.  Cresendo of Doom added the British, which were between the Germans and Americans, and the French, which were between the Americans and the Russians.  The game very much was a leader management drill: the Germans could rally their troops quickly and still have strong leaders lead the attack while the Russian leaders desperately scrambled from one location to another trying to keep the momentum going.  The other nationalities experienced different levels in between.  In ASL, the Germans still lead in the ratio, but the differences are much less pronounced.  Given equal number of squads, the German player will have an edge in quality and quanity of leadership, but not by much.

The other significant change is that ASL uses a step reduction system of casualties (introduced in GI:Anvil of Victory, for those willing to take enough abuse to get there).  In Squad Leader, a stack could be eliminated outright, or it could have to take a morale check.  Those that failed would become broken, and those that were already broken would be eliminated.  In ASL, the X (elimination) result was replaced with 1X, 2X, and 3X, which meant that 1, 2 or 3 units would be eliminated and the rest automatically broken.  Furthermore, a squad that was already broken and failed a morale check would be reduced to a half squad.  Only a broken half squad faced elimination for failing a morale check.

These two changes significantly reduced the mortality rate on the battlefield.  Game play is therefore slower (although not less exciting) and ASL rewards consitantly good play over a lucky kill of a strong point.

The other changes, in my opinion, did not change the feel of the game, but rather led to a smoother process of the game.  Cumbersom rules were streamlined and some were left out altogether.  While it is impossible to cover them all, I will point out three examples in particular.  The first is the elimination of the scout (from Cresendo of Doom).  Instead, half squads can be used to draw enemy fire and a cleaver "search" rule has been added.  Basically, a unit that is searching rolls a 1d6.  This is the number of hexes the unit can NOT search (which should include hexes he knows to be clear).  Any hidden or concealed unit in the remaining hexes must reveal themselves.

The second rule is the re-writing of Sniper rules.  In Squad Leader, the sniper was a 1 fire point unit that could not shoot with anyone else but did have a modifier to the roll.  He rarely did much good unless he had a very large modifer (1 fire point is pathetic in this game, 8 is the minimum effective strength) and could be eliminated realtively easily once found by the enemy (assuming they thought it was worth it).  In ASL, each player has a Sniper Activation Number.  If the opponent ever rolls that number, then there is a chance that the sniper will strike.  And if he does strike, something bad IS going to happen to the other player.  This feature is a real charm to the game, as it adds a fog of war that the opponent can never completely prepare for and actually penalizes him for rolling low (something he would normally want to do).

The third change I want to talk about is allowing the opposing player to defensive fire during the friendly player turn.  In Squad Leader, whenever a unit moved in sight of an enemy, a tracking counter was placed on the map board.  During the defensive fire phase, the defender could bring back that unit to shoot at him.  The problem is the clutter that quickly accumulates in large games and the confusion that results (lord help you remember if several units crossed paths).  Furthermore, this gave the defender a big advantage as he could see everything before deciding how to prioritize his targets.  In ASL, the defender can interrupt the moving player to shoot at a moving unit.  This greatly simplifies the game with the reduction of clutter but simultaneously adds realism and fog of war.  The defender must now decide if he wants to fire at the moving unit or wait for a bigger target that may or may not come.

BUYING GUIDE
The first question you need to ask yourself before buying is if this is the game for me.  If you are a beginner, then I suggest you start with much less complex games (I would recommend the Panzer Grenadier games) to get used to some conventions.  If you do like complex and highly detailed tactical games, then I will tell you that this is the best you will find and that you will get a lifetime of enjoyment out of it.

The next question is "what do I get"?  Unless you start with Starter Kits, you need the rule book and either Beyond Valor or Paratrooper.  From there, you can add to your collection at your own pace, but I do recommend you get the games in order as most modules need things printed in earlier modules (see my notes below).  The Deluxe ASL games are very enjoyable and playing with miniatures adds a lot to the game.  However, the miniatures are very much optional.  You can enjoy DASL without them.

MMP has developed Starter Kits, which is the best way to get introduced to the game.  They are completely self contained, with necessary maps, counters and (simplified) rules to play the scenarios incorporated.  If you like what you have played, then you can pay for the more expensive games in confidence.  You will have to read the official rules to learn what was not covered in the basics.  Each starter kit focuses on a particular type of rule, which would let you use the starter kit in conjunction with the main rules when you want to expand your gaming range.  For example, you have the rule book and Beyond Valor and you have been playing infantry only game.  You are now ready to start on tanks, but feel overwhelmed.  You could buy Starter Kit #3 (which focuses on armor) to get the feel of them.  When you are confident you have the basics down, you can read the core rules and then add tanks to your easter front battles.

I do want to emphesize caution when buying modules.  Rather than flood players with thousands of duplicate counters, later modules required ownership of earlier modules for maps and pieces.  Beyond Valor is required to play virtually any other module (except Paratrooper or the Starter Kits), and Yanks is also one to get early.  As the collection grows from small to mid sized, West of Alamien and Code of Bushido should be purchased.

If buying a copy in the store, be sure to check the back of the game, as it will tell you exactly what is needed to play it.  Sometimes, the description will say "such and such to play all and such and such to play some."  What has happened is that most of the sceanrios can be played with only a few other modules, but that some of the scenarios require specialty pieces from others.  This means you can still enjoy the module until such time as you purchase the specialty pieces.

If buying on-line, you can use my guide below but I still recommend you find out the specifics of what prerequsite modules are requried either by reading the description or asking the seller.  If they won't or can't help, leave them be.  These modules cost too much to be sitting around because you don't have what you need.

While this will not cover every possiblity, here is a safe buying strategy:

1) Buy any starter kit
2) Buy the rule book
3) Buy either Beyond Valor and/or Paratrooper
4) Buy core modules in order up to and including Yanks
5) Buy Streets of Fire and/or Hedgerow Hell
6) Buy any Historical Module EXCEPT Pegasus Bridge
7) Buy core modules in order up to and including West of Alamein
8) Buy Pegaus Bridge
9) Buy remaining core modules
7) Buy Historical Studies modules

I have given a history of the game's development and production, described the basic mechanics of it, compared ASL to the original Squad Leader and given some tips on purchasing the game.  I hope that this has been helpful to you.  Feel free to contact me on the game if you have any further questions.